摘要
为研究冲击载荷作用下煤岩的孔隙与裂隙演化特征,以贵州马场矿的突出煤岩为研究对象,利用分离式霍普金森压杆(SHPB)试验系统、核磁共振(NMR)试验系统和扫描电镜(SEM)试验系统对不同冲击载荷作用下的煤岩孔隙与裂隙的演化特征进行试验研究,分析煤岩在冲击载荷的作用下的孔隙、裂隙的演化规律与煤岩冲击对煤与瓦斯突出的影响。研究表明:随着冲击气压的增加,煤岩的微小孔峰值信号量与孔径占比先增大后减小,孔隙与裂隙的连通性增强,中大孔峰值孔径占比先减小后增大;马场矿煤样微小孔的孔喉分布占总孔喉的38.85%~56.14%,中大孔的孔喉分布占总孔喉的43.86%~61.15%;在冲击载荷作用下,煤体中孔隙与裂隙演化是以孔隙扩展、裂隙扩张与延伸和次生裂隙的产生等形式进行的,冲击载荷增强了孔隙与裂隙的连通性,瓦斯的吸附/解吸平衡被打破,瓦斯压力升高,煤体中产生了应力集中和能量积聚,使得煤与瓦斯突出发生的可能大大增加。
In order to study evolution characteristics of coal pores and fractures under impact loadings,with outburst coal of Machang Mine in Guizhou as a research object,Separate Hopkinson Pressure Bar(SHPB)test system,NMR and Scanning Electron Microscope(SEM)system were utilized to investigate their evolution features under different impact loadings.Then their evolution law and influence of coal impact on coal and gas outburst were analyzed.The results show that with the increase of impact pressure,micro pores’peak value semaphore and diameter ratio increase first and then decrease and connectivity of pores and fractures is enhanced,but peak value diameter ratio of medium and large pores decreases first and then increases.And pore throat distribution of micro pores in Machang Mine accounts for 38.85%~56.14%of the total while that of medium and large ones makes up for 43.86%-61.15%.Under impact loadings,evolution of pores and fractures in coal is carried out in the form of pores expansion,expansion of fractures and formation of secondary fractures.Moreover,impact loading strengthens connectivity of pores and fractures,breaks gas adsorption and desorption balance,causes an increase of gas pressure,and produces stress set and energy accumulation in coal body,thus increasing possibilities of coal and gas outburst.
作者
李胜
王箫鹤
范超军
张浩浩
刘铮
殷坤
LI Sheng;WANG Xiaohe;FAN Chaojun;ZHANG Haohao;LIU Zheng;YIN Kun(College of Mining Engineering,Liaoning Technical University,Fuxin Liaoning 123000,China;State Key Laboratory of Coal Resources and Safe Mining,Xuzhou Jiangsu 221116,China)
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2019年第10期91-97,共7页
China Safety Science Journal
基金
国家自然科学基金资助(51674132)
国家重点研发计划项目(2016YFC0801407-2)
辽宁省教育厅城市研究院项目(LJCl002).
关键词
冲击载荷
孔隙结构
突出煤岩
核磁共振(NMR)
孔喉分布
impact loading
pore structure
outburst coal
nuclear magnetic resonance(NMR)
pore throat distribution
作者简介
李胜(1976—),男,四川资中人,博士,教授,主要从事煤与瓦斯突出防治及矿山压力与岩层控制等方面的研究。E-mail:13914181946@163.com
